I enjoyed this piece from Riana Pfefferkorn, writing in NYU Law’s Just Security, on the implications of a forthcoming iPhone feature called “USB Restricted Mode” that blocks all connections to a computer if the phone hasn’t been unlocked in over an hour. Today, even if the police don’t know the passcode to unlock your phone, they can connect your phone to a special computer that will try all possible passcode combinations from 000000 to 999999 over the span of a few days. This fall, Apple will push an update to iPhones that disables that port, and makes it harder to break into a locked iPhone.

As Pfefferkorn explains, the police don’t need a search warrant if there are what’s called “exigent circumstances” – and if the phone is about to lock everyone out of itself forever, Apple might be shooting itself in the foot:

The 2014 Supreme Court case Riley v. California requires police to get a warrant before searching a smartphone seized from someone who’s been arrested. […] “If ‘the police are truly confronted with a “now or never” situation,’ … they may be able to rely on exigent circumstances to search the phone immediately,” the Court said. Id. at 2487 (citation omitted). DOJ could thus thread the needle by arguing that the mere possibility that USB Restricted Mode is enabled on a seized iPhone creates “a ‘now or never’ situation” necessitating the immediate use of Cellebrite or GrayKey without waiting for a warrant.

Applied broadly to iPhones, this exception would swallow the Fourth Amendment’s general rule. The “we need to dump the phone ASAP just in case USB Restricted Mode is on” approach might fly in a one-off situation. But that uncertainty will probably be present most times police seize a locked iPhone. Under that logic, it would be OK to forensically search any iPhone immediately without a warrant, because there would always be exigent circumstances.

That is not how an exception to a rule works. “Exigent circumstances” are supposed to be situational and case-specific. The DOJ’s own manual for electronic evidence search and seizure acknowledges as much: “in electronic device cases, as in all others, the existence of exigent circumstances is tied to the facts of the individual case.” Given that recognition, DOJ would be hard-pressed to adopt or defend a policy allowing warrantless searches of iPhones a priori in all instances on the rationale that every single time police seize an iPhone, they “are truly confronted with a ‘now or never’ situation” as Riley said. That is particularly so given the alternative ways that police, with a warrant, could get data from a locked, encrypted phone, as a recent law review article about Riley explains—for example, going to the relevant service provider and asking for cloud backups of the phone’s contents.

The Fourth Amendment isn’t exactly my strong suit, so this was an extremely educational read.